<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>XMLSerializer 类型</title>
</head>
<body>
  <script>
    const parser = new DOMParser();
    const xmldom = parser.parseFromString('<root><child /></root>', 'text/xml');
    const serializer = new XMLSerializer();
    const xml = serializer.serializeToString(xmldom);
    console.log(xml);  // "<root><child/></root>"
  </script>
</body>
</html>